Affordable Anti-Jam Technology

In a world where there is more and intentional and unintentional interference with GNSS, it’s a little comforting to hear that technology has been developed which can help us fight back. The proliferation of affordable “Personal  Protection Devices (PPDs)” used to mask GPS location — for users who carry location capability but who really don’t want to be tracked — is already been felt at critical points in our GNSS infrastructure in North America. Well, if you can buy a catalog jammer over the Internet in the U.S., how readily available are these things for terrorists and people waging war against us overseas and at home?

So now NovAtel (Calgary, Canada) and QinetiQ (UK) have come up with a potential remedy for military land vehicles that are taking our forces into harm’s way. The GPS Anti-Jam Technology (GAJT or ‘Gadget’) antenna was just released by NovAtel, and the company will be taking orders in the fall. It’s a fully integrated anti-jam solution in a single, robust package. The price point has not been openly discussed, but there is good possibility that it will be significantly more affordable that existing mil-spec systems, and that makes it possible that this integrated antenna/signal processing system will soon find applications in the civil field, in such applications as hazardous material transport or high-value cargo transportation.

The core of this receiver involves an integration of key technology from both NovAtel, and from QinetiQ. QinetiQ is a UK company few in the commercial world may know well — QinetiQ is better known in military circles for its close support role to the UK Ministry of Defense (MoD), and from the other side of an impenetrable “firewall” the rest of the business has been largely involved in complex R&D support tasks for the same customer. This complex arrangement came about as a result of continuing commercialization of UK government assets, as more activities are pushed down into private industry. More recently, the commercial side of QinetiQ has been looking for ways to bring its vast storehouse of military R&D technology to market, and the marriage with NovAtel for GAJT brought a heap of their radar signal processing IP to the table.

NovAtel’s Pinwheel antenna technology got the original ball rolling when a prototype Controlled Radiation Pattern Antenna (CRPA) element was tested, first in the U.S. and then afterwards in the UK by QinetiQ, who was looking for a small form-factor antenna for UAVs. Great results when tested alongside the Raytheon GAS-1 industry standard CRPA. The flat, circular Pinwheel antenna element actually has seven sub-elements which can be made to work together to find and overcome in-band jamming signals, and its small size and low profile make it ideal for smaller vehicles.

Some time after this initial testing, NovAtel also began talking with the Canadian Department of National Defence (DND), who were already deep into their own CRPA research. After lots of PowerPoint slides and extensive technical discussions, NovAtel cornered a small DND contract to develop their own CRPA, with QinetiQ working their side of the program in parallel in the UK.

The architecture gelled and the program came together, with lots of unexpected twists and turns which are typical of a brand-new concept, and with the development and integration of two different companies’ technologies. Seven time zones apart, the two teams worked well together and solved all the problems thrown at them, to eventually provide DND with prototypes for testing. DND has its own jamming test facilities but DND also participates in a “four-eyes” four-nation (Canada, USA, UK, and Australia) collaboration on anti-jam developments, so military testing sessions under field conditions in the U.S. and Australia were accessible and were used by DND to assess GAJT.

NovAtel is now preparing for initial production with equipment build expected to deliver GAJT units in Q3 and Q4 this year — so this means they are already well advanced in the build and test set-up processes.

As far as marketing, NovAtel and QinetiQ are working together, focusing on potential customers in their existing areas, while NovAtel will actually supply and support the equipment. Clearly, QinetiQ has existing strong connections with UK MoD and other areas of UK influence, while NovAtel has a good presence in North America and elsewhere around the world. They are both focusing on potential military applications first, because this is where there is the greatest number of unprotected land vehicles which are exposed to the greatest risk.

An affordable solution for military land-vehicle fleets presents a real opportunity for commanders to operate without enemy disruption of GNSS navigation. Up to now, the anti-jam solutions available have been too expensive and too bulky to even consider the humble Humvee as a candidate for such a solution. An affordable single unit that can be installed simply could just be a godsend for troops on the ground.

There are a  lot of other manufacturers working in the GPS anti-jam arena, but most appear to be purely military, have a separate antenna and signal processing unit, and the solutions are pricy. Some examples include Thales’ Top Shield anti-jam system targeted at military helicopters; Raytheon’s GAS-1 (the existing anti-jam standard in the field), which finds a number of applications on military fast-jets; and a whole slew of more complex systems (Boeing is working a USAF program which adds an inertial sensor for guided munitions), and less complex solutions using an omni-directional antenna but with sophisticated signal processing to minimize the effects of low-elevation jammers. GAJT is different in that it’s the first high-performance CRPA with fully integrated signal processing in a single, affordable small package. One other key feature is that this equipment is only subject to Canadian and UK export controls. These features promise to allow for eventual introduction in other non-military markets.

Our PPD proponents and the swath of civil infrastructure disruption they create around them — well, this “gadget” might just be an affordable solution for high-value civilian tracking, where its essential that location is known all the time, without the risk of potential lengthy fade-outs. Provided GAJT comes up to its promise of a lower cost, high-performance anti-jam solution in a single easily installed package, we may soon see more civilian vehicle applications such as hazardous material transport, or high value cargo transportation. So help is on the way for us in the civil word, too — we may soon be able to overcome some of our GNSS signal interference and jamming issues.

Tony Murfin
GNSS Aerospace